When he was growing up, Matt Harvey's family made the journey about a half-dozen times.

It began in his hometown of Mystic, Conn., where allegiances often are divided between the Red Sox and Yankees. It usually ended at Shea Stadium, where the Harveys typically got better seats for the Subway Series than they could in the Bronx.

"I dreamed of being involved in that,'' Harvey said Monday. "Now, being a part of it, it's definitely a dream come true.''

Indeed, Harvey sometimes wore his Yankees cap to Subway Series games, where he rooted for his idols, Paul O'Neill and Derek Jeter. But he has long traded it in for a Mets cap, which he will sport on the mound Tuesday night at Citi Field.

"I was walking down the street today and I heard some 'beat the Yankees' and stuff like that. It's always fun,'' said Harvey, who will make his Subway Series debut. "It definitely keeps you going. It keeps the drive strong. Hopefully, we can go out with a couple of wins here.''

With the Mets in fourth place and the offense languishing on a nightly basis, Harvey's starts have been a break from the monotony. But Tuesday night's outing might be his most-hyped appearance of the season thus far.

Even some of the Yankees said they're excited about getting a closer look at the phenom, who is 5-0 with a 1.93 ERA.

"Definitely,'' Vernon Wells said. "It's been fun watching him go to work throughout the season. He's got electric stuff, and I think it's always fun to face guys like that, just to kind of get an up-close view of what he's got and see what we can do against him.''

Harvey's call-up last season came after the Yankees and Mets had concluded the Subway Series. Yankees manager Joe Girardi has been "very impressed'' by what he has seen from Harvey on television.

Said Girardi: "Obviously, his stuff speaks for itself and it really looks like he knows how to pitch and he's pitched really well for the Mets.''

Harvey, 24, is one of three National League pitchers with at least 50 innings who have yet to take a loss this season. Before allowing four runs in his last start against the Reds, Harvey had put together a run of 16 straight outings in which he allowed three or fewer runs.

Harvey's .169 opponents' batting average is the lowest of all qualifying NL pitchers.

"I think everyone in here enjoys facing guys like that just to either make one end of the highlight reel,'' Wells said. "Either you're punching out or getting a hit, so we'll see what happens.''

Harvey said he expects plenty of friends and family in the stands at Citi Field, many of them making the same journey he made as a child. Of course, things have changed. The Yankees cap is long gone and the rest of Harvey's family has shed its old allegiances.